18th International Symposium on Iron Nutrition and Interaction in Plants
Madrid – May 30-June 3 2016
EFFECT OF INTERCROPPING WITH GRAMINACEOUS SPECIES OR FE-HEME APPLICATIONS ON
VEGETATIVE GROWTH, PRODUCTIVE COMPONENTS AND BERRY PHENOLIC COMPOSITION IN
BLUEBERRIES CULTIVATED IN A CALCAREOUS SOIL
Lucía Michel, José I. Covarrubias*
Facultad de ciencias Agronómicas, Universidad de Chile. Av. Santa Rosa 11.315, Santiago, Chile.
*[email protected]
Cultivation and commerce of blueberries (Vaccinium spp.) have currently acquired significant relevance in the
world, mainly due to the high antioxidant compound contents of berries, which are beneficial for the human
health. Iron deficiency is a common nutritional problem in crops cultivated on calcareous and alkaline soils,
being particularly harmful to calcifuges species such as blueberry (Retamales and Hancock, 2012). Iron
deficiency affects blueberry longevity and productivity, root and shoot growth, and berry quality. The most
common management techniques used in the world to correct Fe deficiency are based on the application of
Fe chelates and/or inorganic acids to the soil, which implies high costs and environmental and human health
risks. The main goal of this investigation was to determine, at field level, the effect of sustainable management
techniques for preventing/cure Fe chlorosis on vegetative growth parameters, productive components and
berry phenolic composition in blueberries cultivated in a calcareous soil. Two treatments were evaluated: (1)
application of a bovine blood meal compound (Fe-Heme) and (2) intercropping with the graminaceous species
Festuca rubra and Poa pratensis. Such management techniques were compared with plants not fertilized with
Fe (control), and plants fertilized with a soil-applied Fe-chelate (Fe-EDDHA). The experiment was conducted
during 2014-2015 season on 3 years blueberries cv. Emerald cultivated on a sub-alkaline soil (pH 7.5) with
1% of active lime. Iron-Heme and Fe-EDDHA solutions were manually applied every 15 days from sprouting
until the end of the growth season, with concentrations of 20 g Fe L-1 and 4 g Fe L-1, respectively. Data obtained
indicate that application of Fe-Heme increased leaf area, shoot length, and leaf nitrogen concentration in
blueberries in comparison with the control, and induced a similar total growth in plants compared to the
application of Fe-EDDHA. In contrast, intercropping with Festuca rubra decreased shoot length, summer canes
number and nitrogen, phosphorus and potassium foliar concentrations. Furthermore the association with Poa
pratensis did not significantly modify vegetative growth parameters and leaf mineral concentration in
comparison with the control. These results suggest that the negative effect of intercropping with Festuca rubra
on some of growth parameters could be attributed to the competition exerted by this grass for available water
and nutrients. In this sense, the higher competition capacity of Festuca rubra as compared to Poa pratensis,
is not only due to its higher consumption of minerals but also for its higher aerial biomass production rate. As
for productive components, intercropping with both grasses increased fruit number per plant without affecting
their size, triggering to an increase in plant production in comparison with blueberries treated with Fe-EDDHA
and the control. Such effect was more pronounced in blueberries associated with Festuca rubra. In contrast,
the application of Fe-Heme did not affect plant production in comparison to control plants. In berry skins, the
main anthocyanins identified were delphinidin 3-galactoside, malvidine 3-galactoside, cyanidin 3-galactoside
and delphinidin 3-arabinoside, whereas the predominant low molecular weight phenols were vanillic acid, ciscaffeic acid, astilbin and epicatechin. Furthermore, it was observed that both total and individual phenols and
anthocyanins content in berry skins are directly related to fruit size. Since application of Fe-Heme did not
change fruit size, total or individual content of phenolic compounds in skins was not affected. In contrast,
application of Fe-EDDHA and intercropping with grasses increased fruit weight and induced a higher total and
individual phenol and anthocyanin contents per berry, without affecting their concentration. In conclusion,
intercropping with grasses, in particular with Festuca rubra, seems to be an effective sustainable strategy to
increase fruit production and berry quality in blueberries cultivated in a calcareous soil. Moreover, the
application of Fe-Heme improves vegetative growth of plants, without increasing productivity and berry quality.
Keywords: iron deficiency, calcifugue species, Festuca rubra, Poa pratensis, blood meal compound.
REFERENCES. Retamales and Hancock 2012 Crop Production Science in Horticulture N°21.
ACKNOWLEDGEMENT. This investigation was supported by FONDECYT 11130328 project.
Preferred Presentation format: POSTER.
Selected Sessions: Agronomic practices to correct Fe deficiency: fertilizer development
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